Differences between revisions 1 and 36 (spanning 35 versions)
Revision 1 as of 2007-06-23 18:04:59
Size: 168
Editor: mrt-aod
Comment:
Revision 36 as of 2007-06-24 11:19:39
Size: 2451
Editor: mrt-aod
Comment:
Deletions are marked like this. Additions are marked like this.
Line 1: Line 1:
Tests performed during the heavy maintenance. Tests performed during the heavy maintenance (2007.06.20)

[[TableOfContents]]

=== Goals ===

Identify the origin(s) of the "acceleration" problem in MAMBO2.
   * Is the acceleration problem due to a mechanical or electrical process ?
   * What is the influence of the driving program on its intensity (Basic/Cascade) ?
   * Any difference in the peak noise whether it is an on-off in elevation or in azimuth ?

=== People ===
Line 4: Line 15:
Goals: Identify the origin(s) of the "acceleration" problem in MAMBO2 [[BR]]
People: DJ, SL, SN, JP
Pico Veleta: DJ, SL, SN, JP
Line 9: Line 19:
Methods === Methods ===

   * An inclinometer was installed on the Mambo2 platform (see picture below) to measrue the vibrations during the measurements.

attachment:inclinometerPhoto.jpg
----------
   * On-off measurements on an absorber. The on-off are done w/o the wobbler taking offset in azimuth and elevation to activate the Basic or Cascade controller. The Basic/Cascade limits are (600,400) arcsec in (Azimuth,Elevation). We point out that these observation are not reproducing exactly the standard bolometer observations with wobbler and a throw < 90 arcsec.

   * An extra weight was added on the bolometer platform to check the effects of a change in the platform response to the vibration.


   * Oscilloscope monitoring directly on Mambo2 was performed during an on-off measurements.

   * You can find the list of the absorber on-off scans [:AbsorberTests: here]





=== Results ===

   * Inclinometer measurements for two on-off measurements with the Cascade and the Basic controller.

[[BR]]
attachment:inclinometerBolo.jpg

Clearly the Basic controller leads to movements smoother than with the Cascade controller. On the bottom panel the inclinometer measurements indicate

   * On-off measurements with the offsets in elevation: 360" (scan 47, Cascade) and 440" (scan 50, Basic)

[[BR]]
'''Cascade controller'''
attachment:scan47-elev-cascade.jpg
---------
'''Basic controller'''
attachment:scan50-elev-basic.jpg
---------

   * An extra weight was put on the bolometer platform (scan 51)
attachment:scan51.jpg
---------

   * Measurements of electrical peak with the oscilloscope during an on-off measurements with the offsets in elevation (scan 53).
No correlation was found between the beginning of the scans where the extra noise peaks appeared and the electric activity. A peak frequency of 5 sec
was observed but which may be related to the air conditioned system.


 
=== Conclusions ===


   

Tests performed during the heavy maintenance (2007.06.20)

TableOfContents

Goals

Identify the origin(s) of the "acceleration" problem in MAMBO2.

  • Is the acceleration problem due to a mechanical or electrical process ?
  • What is the influence of the driving program on its intensity (Basic/Cascade) ?
  • Any difference in the peak noise whether it is an on-off in elevation or in azimuth ?

People

Pico Veleta: DJ, SL, SN, JP

Methods

  • An inclinometer was installed on the Mambo2 platform (see picture below) to measrue the vibrations during the measurements.

attachment:inclinometerPhoto.jpg


  • On-off measurements on an absorber. The on-off are done w/o the wobbler taking offset in azimuth and elevation to activate the Basic or Cascade controller. The Basic/Cascade limits are (600,400) arcsec in (Azimuth,Elevation). We point out that these observation are not reproducing exactly the standard bolometer observations with wobbler and a throw < 90 arcsec.

  • An extra weight was added on the bolometer platform to check the effects of a change in the platform response to the vibration.
  • Oscilloscope monitoring directly on Mambo2 was performed during an on-off measurements.
  • You can find the list of the absorber on-off scans [:AbsorberTests: here]

Results

  • Inclinometer measurements for two on-off measurements with the Cascade and the Basic controller.

BR attachment:inclinometerBolo.jpg

Clearly the Basic controller leads to movements smoother than with the Cascade controller. On the bottom panel the inclinometer measurements indicate

  • On-off measurements with the offsets in elevation: 360" (scan 47, Cascade) and 440" (scan 50, Basic)

BR Cascade controller attachment:scan47-elev-cascade.jpg


Basic controller attachment:scan50-elev-basic.jpg


  • An extra weight was put on the bolometer platform (scan 51)

attachment:scan51.jpg


  • Measurements of electrical peak with the oscilloscope during an on-off measurements with the offsets in elevation (scan 53).

No correlation was found between the beginning of the scans where the extra noise peaks appeared and the electric activity. A peak frequency of 5 sec was observed but which may be related to the air conditioned system.

Conclusions

testMambo-20070620 (last edited 2009-04-16 08:26:28 by localhost)